Glass bending mold



July 27, 1965 R. JOHNSTON 3,197,298

GLASS BENDING MOL`D 77- far/vr@ July 27, 1995 R JOHNSTON ETAL 3,197,298

GLASS BENDING MOLD 3 Sheets-Sheet 2 Filed Dec. 13. 1960 INVENTORS'AWywff 0227715.51271 .yB/vwes 7i Jaz/za July 27, 1955 JOHNSTON ETAL3,197,298

GLASS BENDING MOLD Filed Dec. 13, 1960 3 `Sheets-Sheet 5 i fran/V57@United States Patent O 3,197,298 GLASS BENDNG MOLD I Raymond Johnston,Southfield, and James P. .lulro,r{.)ak

Park, Mich., assignors to Chrysler Corporation, hughland Park, Mich., acorporation of Delaware Filed Dec. 13, 196i), Ser. No. '75,521 10Claims. (Ci. 65-291) This invention relates to glass bending molds ofthe so-called fioating center section type wherein the floating centersection is pivotally connected at its opposite ends towing sectionshaving novel support means for effecting the vertical floating movementof the intermediate center mold section.

It is a primary object of this invention to provide support means forthe wing sections of a floating center section glass bending moldwherein a simplified yet accurate control of the movement of the glassduring bending is obtained and wherein the arrangement of the mold onthe support frame is such that accurate bending is achieved.

It is another object of this invention to floatingly support the bendingmold forming surfaces on the mold frame in such a manner that distortionof the frame during handling will not aect the accuracy of the glassbending operation because of the novel interconnection between the moldbending and the associated supporting frame.

It is another object of this invention to connect a tloating centersection bending mold to a mold supporting frame by means of rollers onthe mold bending ring that are movably mounted on the ring supportingframe,

It is still another object of this invention to connect a sectionalizedoating center section bending ring with a mold supporting frame by meansof intermeshed relatively movable gearing that accurately controls glassbending while eliminating distortions of the glass that might resultfrom variations or deflection of the supporting trame.

It is still another object of this invention to associate a thermallycontrolled torsion spring means with the pivotally mounted wing sectionsof a sectionalized floating center section ring type glass bending mold.

It is still another object of this invention to loosely interconnectcertain sections of a sectionalized bending mold with an independentsupport frame by means of pin mounted rollers wherein limited relativemovement may occur between the roller mounting pins and track formationson the support frame.

Other objects and advantages of this invention will he readily apparentfrom a consideration of the following description and the relateddrawings wherein:

FIG. 1 is a side elevation of a sectionalized iioating center sectionglass bending mold embodying a preferred form of this invention, themold being shown in open position prior to bending of the glass sheetsupported thereon;

FIG. 2 is a side elevational View of the glass bending mold shown inFIG. 1, this View being taken with the mold in closed position at thecompletion of a glass bending operation;

FIG. 3 is a top plan view of the mold shown in FIGS. 1 and 2 with themold forming surface shown in closed position as in FIG. 2;

ice

ing means;

FIG. S is a fragmentary end elevational view of the FIG. 7 mold wingsection supporting means, this View being taken in the direction of thearrow C of FIG. 7; and

FIG. 9 is a fragmentary side elevational view of still another form ofmold wing section supporting means.

In the bending of fiat sheets of glass or similar material, to formcurved glass articles such as motor vehicle windshields or the like, itis conventional practice to support a flat sheet of glass G (see FIG. 1)on a glass bending mold ring R that is supported on a mold frame F thatis passed through a glass bending lehr (not shown) of appropriate type.The mold frame F with Yits supported bending ring R is passed throughthe glass bending lehr by conveyor means and mold transfer means thatroughly handles the frame F during the glass bending operation.V As themold ring R and supporting frame F are heated to temperatures of 1000"to l200 F. during the glass bending operation it has been found thatrough handling of the bending mold frame while it is in its heatedcondition or shortly thereafter has a tendency to cause deflections inthe framework F that might be transmitted to bending ring R such thatinaccurately shaped bent glass articles might be produced.

It is a prime object of this invention to fioatingly support the bendingring R on the frame F such that any minute distortions or deflections ofthe frame F will not be directly transferred to the bending ring R andthus will not interfere with accurate bending of the glass G. Inaddition to providing accurate control of the glass bending operation,the novel mold means herein disclosed also uses a minimum of structureso as to provide a low cost bending fixture that is least susceptible toproblems associated .with thermal capacities of the mold because of theminimum amount of metal involved in the mold structure. Also, therelative movement between the floating center section 1t) and thepivotally connected relatively movable wing sections 11 and 12 providesextreme exibility during the glassbending operation while at the sametime insuring accurate shaping of the glass G when the sectionalizedmold ring R has moved to closed position (see FIG. 2) at the completionof the glass bending operation. A

The form of this invention shown in FIGS. 1 through 5 will be describedin detail first and then the modified forms thereof shown in FIGS. 6through 9 will be thereafter described to point out the distinctionsbetween the several forms of this invention which forms all embody thesame bending concept.

In FIGS. 1 through 5 the glass bending mold comprises a framework F ofrectangular plan configuration (see Patented July 27, 1965 FIG. 3)formed from opposed tubular side rails 15 and 16 and opposed tubular endrails 17 and 1S which rails are arranged to provide a rectangularframework. The frame F may include the depending legs 2t) and 21 thatare adapted to ride upon any conventional type of glass bending lehrconveyor mechanism (not shown). EX- tending upwardly from the Oppositeends of the frame F, at each side thereof, are a pair of ring supportingpedestals 22 and 23, respectively. The pedestals 22 and 23'are of thedesign shown in detail in FIGS. 4 and 5. It will be noted from FIGS. 4and 5 that the pedestal 23 has a cap 26 that includes a rectangulargroove 27 ero tending lengthwise across its top surface which groove isblocked at its opposite ends by suitable stop means 28. The groove 27 isadapted to seat a roller 29 that is journalled on a pin or rod 30carried by the associated substantially U-shaped wing section 11 of themold glass shaping ring R. It is thought to be obvious from thedescription so far that the roller 2.9 can have rolling and/or slidingmovement in the groove 27 of the frame pedestal 23. Furthermore, fromFIG. 5, it will be noted that the roller groove 27 in the pedestal cap26 is greater than the Width of the roller 29 so that there is asuicient clearance between the roller and the groove sides to allow forslight misalignments, deections and/or distortions of the frame Fwithout transmitting the effects of these misalignments, distortions ordeflections to the roller supported glass bending ring R.

The mold ring R comprises a center section that includes the strip-likeside rails 41, 42 that are intercon nected by suitable cross bracing 43.The mold ring wing sections 11 and 12 are formed of a substantiallyU-shaped strip 46 that is cross braced as shown at 47. Y Each wingsection 11 and 12 also includes the pivot bar that mounts theaforementioned support rollers 29. Suitable hinge means 50 (see FIG. 4)pivotally interconnect the wing sections 11 and 12 to the opposite endsof intermediate or center mold ring section 10. The adjacent end edges51- and 52 of the mold ring sections 10, 11

and 10, 12 (see FIG. 4) are adapted to abut and limit fthe closingmovement of the wing sections 11, 12 with respect to the center section1i).

Looking at FIG. l, which shows the mold ring R in open position with theglass G supported thereon, it is thought to be obvious that the weightof the glass G is suicient to maintain the wing sections 11, 12 in theopen position. As the mold passes through a bending lehr the temperatureofthe glass G is raised to such a temperature that the glass softens andunder such circumstances the Weight of the mold ring is suicient tocause the mold wing sections 11 and 12 to begin a gradual upward bendingmovement so that they will eventually reach the closed position shown inFIG. 2. During this movement from the open position shown in FIG. 1 tothe closed position shown in FIG. 2 the ring support rollers 29 rolland/ or slide along the pedestal trackway grooves 27 to accommodaterelative movement between the ring center section 10 and the pivotallyconnected wing sec tions 11 and 12. The freedom of movement afforded thewing sections 11, 12 with respect to the center` section 1i) by virtueof the roller and track connection 29, 27 accommodates any variation istemperature at opposite ends of the mold ring as well as any variationin material composition that would tend to cause one wing section tomove at a greater or lesser rate than the other wing section. The freeoating movement of the mold ring sections provides maximum flexibilitywitlrminimum structure and eliminates the transmission of any framedistortion to the glass shaping ring R. FIG. 6 is quite similar to theFIGS. 1 through 5 form of the invention, but differs therefrom in that acam block 6d having an arcuate rolling surface 61 is mounted on the moldring wing sections 11 and 12 by welding 62 or any similar attachmentmeans. This cam block 6-9 takes the place of the journal pin mountedrollers 29 shown in the FIGS.

d. l through 5 form of the invention. The cam surface 61 of cam block61) is arranged to roll and/ or slide lengthwise of the trackway groove27 in the cap 26 of pedestal 23. rhe opposite ends of the groove 27 areblocked by suitable stop means 2S so as to limit the movement of the camblock relative to the grooved trackway 27.

FiGS. 7 and 8 show still a third form of this invention wherein gearmeans 65, 66 is substituted for the wing section supporting means 29 or60 previously described with respect to the two aforementioned forms ofthis invention. In the FIGS. 7 and 8 form, the mold ring Wing sections11 and 12 each carry an axle pin 71 that fixedly mounts a gear 65. Thepin 71 extends through an elongated slot 73 provided in the upper end ofthe pedestal 23. Pin 71 thus can have a limited shifting movementlengthwise of the mold frame F by virtue of the pin and slot connection71, 73. Gear is arranged to meshingly engage a gear element 66 that is1izeyed at 74 to a rotatable shaft 75. Shaft 75 is journalled in thepedestal 23 of the frame member F. A coiled torsion spring 77 has oneend thereof anchored at 73 to the rotatable shaft 75 and the oppositeend of the coil spring is anchored to the fixed pedestal 23' as shownat'79. The function of the coil spring 77 is to act through the shaft 75and the meshed gears 66, 65 to rotate the associated wing section of themold 11 or 12 upwardly to closed position. As the glass G softens duringthe heat treatment in the bending lehr, the action of the torsion spring77 combines with the weight of the mold ring R and the supported glass Gto effect lowering of the mold center section 1G on upward foldingmovement of the mold wing sections 11, 12. to their finalized closedpositions. The coiled torsion spring 77 may be thermally responsive suchthat as the temperature is raised in the bending lehr the force exertedby the spring is increased and there is an increase in force applied tothe ends of the glass G to bend the end portions upwardly to theirnalized form.

FIG. 9 shows a still further modified form of the invention which issimilar in some respect to the form shown in FIGS. 7 and 8 in thatidentical gear means 65, 66 are used and these gear means are supportedon the pedestal 23 in the same manner as shown and described withrespect to the FIGS. 7 and 8 form of the invention. The FIG. 9 form ofthe invention differs from the FIGS. 7 and 8 forms in that a leversupported weight 80 is connected to the rotatable gear shaft 75 ratherthan using a torsion spring to effect rotation of the gear element 66.The Weight 80 provides a constant force rather than a variable forcesuch as that produced by the torsion spring 77.

It is thought to be obvious that the two forms of the invention shown inFIGS. 7, 8 and in FIG. 9, respectively, will each function in a mannersimilar to that already described with respect to FIGS. 1 through 6. TheFIGS.

` 7 through 9 forms permit longitudinal shift of the mold wing sections11, 12 and the attached center section 10 during glass bending due tothe elongated slot and pin connection 71, 73 between the wing sectionpivot pins 71 and slot 73 in the associated frame pedestal 23. Thespring element 77 and the weight element 80 provide additional meansmovement control associated with the pivotally mounted wing sections 11,12 and assist in controlling the time and rate of bending with respectto temperature ofthe glass G.

From the above description of the several forms of this invention, it isthough to be obvious that the floating mold ring R that is supported bybut not fixedly connected to the frame F, provides a distinct advantagefrom both an operational and an economic standpoint. As previous- -lypointed out distortion of the frame F will not be directly transferredto the floating mold ring R because of the clearance t between the moldring support means 29, 6i) or 71 and the associated frame pedestals 23or 23. Also, because of this loose connection the same frames F can beused with different mold rings or vice versa and thus maximum life maybe obtained for the various elements that make up the complete moldunit. Also, the use of a floating mold ring wherein the Wing sectionsare movably mounted on the mold support frame by roller means that'control movement but avoid the transfer of frame distortions is thoughtto be a novel feature that tends to insure accurate glass bending.

We claim:

1. A mold for bending a glass sheet or the like comprising a ring-likeshaping surface to support the glass sheet composed of pivotallyinterconnected intermediate and end ring sections arranged to form aclosed sheet shaping ring having upwardly angled end portions when saidsections are in the closed ring position with said end sections beingfoldable downwardly relative to s-aid intermediate section abouthorizontally extending pivot axes to sheet receiving open ringpositions, an independent frame for floatingly supporting saidring-'like shaping surface including pedestal sections positionedadjacent each ring end section, and pin carrier and slotted trackconnector means interconnecting the shaping ring end sections and saidpedestal sections to provide for .relative movement therebetweenlengthwise of the frame during movement of the ring end sections betweensaid open and closed ring positions, said interconnecting meanscomprising a carrier mounted on each of the ring end sections and atrack mounted on each of the pedestal sections to support the engagedcarrier and accommodate the relative movement therebetween and gearingconnected between each carrier and the associated pedestal to controlsaid relative movement.

2. In a sheet bending mold as set forth in claim 1 wherein said gearingcomprises a pair of meshing gears mounted respectively on saidinterconnected pedestal and ring Sections with one of said gears havinga means connected thereto continuously acting to effect rotation of saidother gear in a direction to cause upward folding movement of theassociated ring and section to said closed position.

3. In a sheet bending mold as set forth in claim 1 wherein said gearingcomprises a pair of meshing gears mounted respectively on saidinterconnected pedestal and ring sections with one of said gears 'havinga means connected thereto continuously acting to effect rotation of saidother gear in a direction to cause upward folding movement of theassociated ring end section to said closed position, said last-mentionedmeans comprising a tensioned spring.

d. In a sheet bending mold as set forth in claim 1 wherein said gearingcomprises a pair of meshing gears mounted respectively on saidinterconnected pedestal and ring sections with one of said gears havinga means connected thereto continuously acting to eifect rotation of saidother gear in a direction to cause upward folding movement of theassociated ring end section to said closed position, said last-mentionedmeans comprising a tensioned spring that is responsive to temperaturevariations.

5. In a sheet bending mold as set forth in `claim 1 wherein said gearingcomprises a pair of meshing gears mounted respectively on saidinterconnected pedestal and ring sections with one of said gears havinga means connected thereto continuously acting to effect rotation of saidother gear in a direction to cause upward folding movement of theassociated ring end section to said closed position, said last-mentionedmeans comprising a weighted crank arm.

In a glass bending mold having a pair of pivotally interconnected glasssupporting shaping surfaces, an independent frame to iioatingly supportsaid surfaces for movement relative thereto comprising a pedestal, andpin and slot means interconnecting said shaping surfaces and saidpedestal comprising a pin roller member mounted on one of said shapingsurfaces and a slot cam surface on said frame pedestal engaged by saidroller member whereby movement of said roller member across said cam sirface lengthwise of the frame accompanies 6 relative pivotal movementbetween said interconnected glass supporting shaping surfaces betweenpredetermined limiting positions, and gearing connected between saidroller member and pedestal operable to control rotation thereof.

7. In a glass bending mold having a pair of pivotally interconnectedglass supporting shaping surfaces, an independent frame to oatinglysupport said surfaces for movement relative thereto comprising apedestal, and pin and slot means interconnecting said shaping surfacesand said pedestal comprising a pin roller member mounted on one of saidshaping surfaces and a slot cam surface on said frame pedestal engagedby said roller member whereby movement of said roller member across saidcam surface lengthwise of the frame accompanies relative pivotalmovement between said interconnected glass supporting shaping surfacesbetween predetermined limiting positions, and gearing connected betweensaid roller member and pedestal operable to control rotation thereof,said gearing having means connected thereto to effect gear rotation.

8. In a glass bending mold having a pair of pivotally interconnectedglass supporting shaping surfaces, an independent frame to oatinglysupport said surfaces for movement relative thereto comprising apedestal, and pin and slot means interconnecting said shaping surfacesand said pedestal comprising a pin rol-ler member mounted on one of saidshaping surfaces and a slot cam surface on said frame pedestal engagedby said roller member whereby movement of said roller member across saidcam surface lengthwise of the frame accompanies relative pivotalmovement between said interconnected glass supporting shaping surfacesbetween predetermined limiting positions, and gearing connected betweensaid roller member and pedestal operable to control rotation thereof,said gearing having means connected thereto to eifect gear rotationcomprising tensioned spring means.

9. ln a glass bending mold having a pair of pivotally interconnectedglass supporting shaping surfaces, an independent frame to floatinglysupport said surfaces for movement relative thereto comprising apedestal, and pin and slot means interconnecting said shaping surfacesand said pedestal comprising la pin roller member mounted on one of saidshaping surfaces and a slot cam surface on said frame pedestal engagedby said roller member whereby movement of said roller member across saidcam surface lengthwise of the frame accompanies relative pivotalmovement between said interconnected glass supporting shaping surfacesbetween predetermined limiting positions, and gearing connected betweensaid roller member and pedestal operable to control rotation thereof,said gearing having means connected thereto to effect gear rotationcomprising a weighted crank arm.

1t). A mold for bending a glass sheet or the like comprising anarticulated, ring-like shaping surface to support the glass sheetcomposed of pivotally interconnected intermediate and end ring lsectionsarranged to form a substantially horizontally disposed, closed sheetshaping ring having upwardly angled end portions when said sections arein the closed ring position with said end sections being foldabledownwardly relative to said intermediate section Iabout horizontallyextending pivot axes to sheet receiving open ring positions, anindependent frame for floatingly supporting said ring-like shapingsurface including pedestal sections positioned adjacent each ring endsection, and pin and slot connector means interconnecting the shapingring end sections and said pedestal sections to provide for relativemovement therebetween lengthwise of the frame duringmovement of the ringend sections between said open and closed ring positions, saidinterconnecting means comprising a pin roller carried by each end ofeach of said ring end sections and va slot in each of said pedestalsections receiving one of said pin rollers and arranged to accommodatethe relative movement '.7 5% therebetween, and gearing connected betweeneach pedes- 2,856,734 l/SS Richardson 65-291 tal and the associated pinroller to 'control movement of 2,872,756 2/ 59 Iendrisak 65-290 the ringend section connected thereto. FOREIGN PATENTS References Cited by theExaminer 5 710,393 6/5-4 Great Britain.

538,160 5/55 Belgium. UNITED STATES PATENTS 810,379 3/59 Grearrirain.V2,551,606 5/51 Jendrisak 65-291' 2,774,189 12/ 56 .Tendrisak 65-290DONALL H. SYLVESTER, Primary Examiner. 2,814,164 11/57 Carson et al.65-290 ALLEN B. CURTS, Examiner.

1. A MOLD FOR BENDING A GLASS SHEET OR THE LIKE COMPRISING A RING-LIKESHAPING SURFACE TO SUPPORT THE GLASS SHEET COMPOSED OF PIVOTALLYINTERCONNECTED INTERMEDIATE AND END RING SECTIONS ARRANGED TO FORM ACLOSED SHEET SHAPING RING HAVING UPWARDLY ANGLED END PORTIONS WHEN SAIDSECTIONS ARE IN THE CLOSED RING POSITION WITH SAID END SECTIONS BEINGFOLDABLE DOWNWARDLY RELATIVE TO SAID INTERMEDIATE SECTION ABOUTHORIZONTALLY EXTENDING PIVOT AXES TO SHEET RECEIVING OPEN RINGPOSITIONS, AN INDEPENDENT FRAME FOR FLOATINGLY SUPPORTING SAID RING-LIKESHAPING SURFACE INCLUDING PEDESTAL SECTIONS POSITIONED ADJACENT EACHRING END SECTION, AND PIN CARRIER AND SLOTTED TRACK CONNECTOR MEANSINTERCONNECTING THE SHAPING RING END SECTIONS AND SAID PEDESTAL SECTIONSTO PROVIDE FOR RELATIVE MOVEMENT THEREBETWEEN LENGTHWISE OF THE FRAMEDURING MOVEMENT OF THE RING END SECTIONS BETWEEN SAID OPEN AND CLOSEDRING POSITIONS, SAID INTERCONNECTING MEANS COMPRISING A CARRIER MOUNTEDON EACH OF THE RING END SECTIONS AND A TRACK MOUNTED ON EACH OF THEPEDESTAL SECTIONS TO SUPPORT THE ENGAGED CARRIER AND ACCOMMODATE THERELATIVE MOVEMENT THEREBETWEEN AND GEARING CONNECTED BETWEEN EACHCARRIER AND THE ASSOCIATED PEDESTAL TO CONTROL SAID RELATIVE MOVEMENT.